This section is intended to provide a background or context to the invention that is recited in the claims. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived, implemented or described. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
In wireless communication, different collections of communication protocols are available to provide different types of services and capabilities. High speed packet access (HSPA) is one of such collection of wireless communication protocols that extends and improves the performance of existing UMTS (universal mobile telecommunications system) protocols and is specified by different releases of the standard by the 3rd generation partnership project (3GPP) in the area of mobile network technology. The other non-limiting example wireless communication protocols are long term evolution (LTE), global system for mobile (GSM) and worldwide interoperability for microwave access (WiMAX).
Current and future networking technologies continue to facilitate ease of information transfer and convenience to users. In order to provide easier or faster information transfer and convenience, telecommunication industry service providers are developing improvements to existing networks. Carrier aggregation technology has drawn considerable attention in, e.g., HSPA and LTE.
In Release 8 (Rel-8) of HSPA standardization of 3GPP, dual-carrier HSDPA (high speed downlink packet access) was specified by introducing dual-carrier operation in the downlink on adjacent carriers. In an example embodiment, dual-carrier HSPA may be used where a MAC (medium access control) scheduler may allocate two HSPA carriers in parallel and double the communication bandwidth. Besides the throughput gain from double the bandwidth, some diversity and joint scheduling gains may also be expected. This can particularly improve the quality of service (QoS) for end users in poor environment conditions that cannot be gained from other techniques Similar idea is under consideration in the enhanced LTE technology called LTE-Advanced. Via this technology LTE is expected to improve end-user throughput, increase sector capacity, reduce user plane latency, and consequently offer superior user experience with full mobility.
In Release 9 studies of the HSPA track, a study item termed DC-HSUPA (dual-cell high speed uplink packet access) for uplink dual carrier UE (user equipment) operation has been launched. In DC-HSUPA, the UE may be assigned one or two adjacent uplink carriers for data transmission if the UE is dual carrier capable. As compared to downlink dual-carrier operation, where the UE is required to receive the dual-carrier transmission transmitted by the Node B or base station, in the uplink the UE is power limited and thus it needs to share its transmission power among the carriers if it transmits on both carriers simultaneously.